1. Field of the Invention
The present invention relates to an information retrieval terminal for use with an information retrieval device for retrieving information, such as text information, by using keywords. More particularly, the invention relates to an information retrieval terminal for extracting keywords from information in surrounding of the information retrieval terminal and for instructing an information retrieval device to retrieve by using the extracted keywords.
2. Description of the Related Art
In today's information society, the importance of information is being reconsidered. Accordingly, techniques for retrieving desired information from a database storing a large amount of information are becoming more and more important. Hitherto, retrievers (searchers) experienced in special retrieval techniques have retrieved. Due to the widespread use of the Internet, however, it has become normal for general users to retrieve by using information retrieval devices. Generally, however, it is difficult for general users to specify suitable keywords and to find desired information. Accordingly, many known techniques for assisting users to specify keywords have been proposed. Such techniques are largely divided into the following three categories:
(1) using dictionaries of synonyms, thesauruses, and related terms (for example, see Japanese Unexamined Patent Application Publication No. 5-28199 (page 2, FIG. 1) and Japanese Unexamined Patent Application Publication No. 6-309362 (page 2, FIG. 1));
(2) using retrieval logs and user profiles (for example, see Japanese Unexamined Patent Application Publication No. 6-314296 (page 2, FIG. 1)); and
(3) using previous retrieval results (for example, see Japanese Unexamined Patent Application Publication No. 10-232870 (page 1, FIG. 3)).
The above-described techniques are similar in that keywords not considered by the users are provided and used for keywords for retrieving information. However, resources for extracting keywords are different, and thus, advantages obtained by these techniques are also different.
Although it has become common for general users to retrieve information, it is often the case in which expected retrieval results cannot be obtained unless the specified keywords are suitable.
In the method using a dictionary of, for example, synonyms, since a systematized dictionary is used as a resource, keywords can be always provided stably. However, since such a dictionary is fixed, the same keywords may be presented to a user who may have another intention for retrieval.
In the method using a retrieval log, since behavior patterns based on individual users are managed, different keywords can be presented to different users. However, even when a user wishes to retrieve with a behavior pattern different from the usual pattern, keywords similar to those based on the usual pattern are presented to the user.
In the method using a user profile, keywords matching the user profile can be presented. However, if the user has a retrieving intention different from attribute information registered in the profile, the profile must be updated, which needs a high cost to maintenance.
In the method using previous retrieval results, different keywords depending on documents obtained by the previous retrieval results can be presented. However, the user has to read all of the results documents to check whether each document matches a desired document.
Accordingly, in view of the above-described problems, it is an object of the present invention to achieve the provision of keywords reflecting the intention of a user, i.e., a retriever, by using information around the user.